NodeManager.java example

Explorer
presto-master
/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.facebook.presto.spi;

import java.util.Set;

import static com.facebook.presto.spi.StandardErrorCode.NO_NODES_AVAILABLE;

public interface NodeManager
{
    Set<Node> getAllNodes();

    Set<Node> getWorkerNodes();

    Node getCurrentNode();

    String getEnvironment();

    default Set<Node> getRequiredWorkerNodes()
    {
        Set<Node> nodes = getWorkerNodes();
        if (nodes.isEmpty()) {
            throw new PrestoException(NO_NODES_AVAILABLE, "No nodes available to run query");
        }
        return nodes;
    }
}